What is the ruling on financial dealings with a scholarship that stipulates a large penalty in the event of a student's withdrawal, and is it permissible to receive this scholarship at the Egyptian Post Office building, which is known for its usurious dealings?

If the fine is equivalent to the amount spent on the student or the damage incurred by the sponsoring entity, then there is no objection. Anything beyond that falls under financial punishment (ta'zeer bi al-mal), which is prohibited according to the majority of scholars. Dealing with someone whose wealth is mixed (halal and haram) is permissible.